Celebrities and family members respond to the Vanity Fair cover featuring Caitlyn Jenner, formerly Bruce Jenner.

INTERNET (JUNE 1, 2015) (REUTERS) – Instagram, Twitter and Facebook were abuzz on Monday (June 1) following the revelation by Bruce Jenner – who is transitioning to life as a woman – of her new name, Caitlyn Jenner, as she posed in a white strapless leotard on the cover of Vanity Fair magazine.

Jenner’s extended family took to Twitter to herald Caitlyn, whose own maiden tweet read “Welcome to the world Caitlyn. Can’t wait for you to get to know her/me.”

Other celebrities who voiced their support online included Ellen DeGeneres, Lena Dunham and Sam Smith. Jesse Tyler Ferguson, who plays a gay man on TV sitcom “Modern Family,” wrote “Caitlyn Jenner has truly broken the Internet. What a moment.” And indeed, it was a moment for Twitter as Caitlyn Jenner broke the online app’s record for fastest growing account, amassing over 1 million followers in just over four hours, beating out the previous record holder, U.S. President Barack Obama.

The cover portrait, by renowned photographer Annie Leibovitz, was taken in Jenner’s Malibu, California home for Vanity Fair’s July issue. The magazine will also feature other high fashion photos of Jenner.

The 65-year old former Olympic athlete and reality TV star has become the most high-profile American to identify as transgender, making the announcement in an interview with ABC’s Diane Sawyer in April.

Jenner, who has been prominently featured as the patriarch on E! Entertainment’s “Keeping Up with the Kardashians,” will star in an E! documentary this July chronicling her new life as a woman.